This invention relates generally to comminuting devices, and more particularly to devices for comminuting organic matter including vegetation such as leaves. This invention relates specifically to devices useful in mulching leaves.
In most of the areas of the world where deciduous trees grow, it is a common practice among the owners of the tree-bearing land, particularly in residential areas, to remove fallen leaves from the landscape. This process is time consuming and often arduous, particularly in the instance where the person engaging in the removal of the leaves is of advanced age.
Recently, a variety of devices have been developed which employ some motive means for picking up and retaining a quantity of the leaves in a storage sack attached to the machine. This process, while superior to manual leaf removal by raking or the like, does not address the problem of removing the leaves from the premises. Thus, large sacks of leaves must be assembled, sealed and physically carried off the premises.
It is also well known that the organic matter constituting the leaves provides an excellent fertilizing medium, if properly fermented or decayed. In this connection, it has been common practice to place organic matter such as leaves and the like in a hole in the ground, known as a compost pile, to permit fermentation to occur over an extended period of time. An alternate approach has been to comminute the leaves into a fine particulate consistency, to form a "mulch" thereof which may then be evenly spread like granular fertilizer over the surface of the lawn, at the base of shrubbery, as well as being incorporated into tracts of land used for growing annual crops. A further utility for the "mulch" comprises the placement thereof into the aforementioned compost pile to allow fermentation to occur, after which the fermented mulch may be employed as formerly suggested in the manner of an organic fertilizer.
Devices for comminuting material such as organic matter are also known. A conventional lawn mower can be employed to comminute leaves while retrieving them from the ground. This is particularly so in view of the present rotary-type mowers which employ collector sacks associated with the cutting outlets on the mower housing.
One difficulty that has attended the employment of lawn mowers as leaf mulchers, has been the inability to control the consistency and direction of the leaves during the comminuting process, and to prevent frequent breakdown of the process due to clogging of the devices. Thus, lawn mowers have conventionally been provided with gratings defining a plurality of smaller holes, which are then installed over the large grass outlets to assist in the mulching operation. These devices have the shortcoming that the particles are insufficiently comminuted, and frequently clog the openings in the grate, with the result that the grate must be frequently cleaned during use.
Certain prior art devices relating generally to the area of the present invention are known which are believed pertinent. Thus, U.S. Pat. No. 2,692,466 to Brunts et al relates to a disc type lawn mower which employs a plurality of chains depending from the rear edge of the lawn mower at spaced apart intervals to prevent objects placed in motion during the operation of the lawn mower from escaping the lawn mower housing and injuring the operator. Likewise, U.S. Pat. No. 3,369,350 to Rogers et al relating to a shredder implement, employs a plurality of chain members again disposed in spaced apart relationship to each other which serve to prevent material being shredded from being thrown forward of the shredding device. None of the foregoing references appreciates the utility or specific construction of the present device.